Campus Units
Animal Science, Food Science and Human Nutrition
Document Type
Article
Publication Version
Accepted Manuscript
Publication Date
11-2016
Journal or Book Title
Journal of Animal Science
Volume
94
Issue
11
First Page
4688
Last Page
4703
DOI
10.2527/jas.2016-0756
Abstract
Heat stress (HS) results in major losses to the pork industry via reduced growth performance and possibly carcass fat quality. The experimental objective was to measure the effects of HS on the pig’s response to dietary fat in terms of lipid digestion, metabolism, and deposition over a 35 d finishing period. A total of 96 PIC 337 × C22/C29 (PIC, Inc., Hendersonville, TN) barrows (initial BW of 100.4 ± 1.2 kg) were allotted randomly to 1 of 9 treatments arranged as a 3 × 3 factorial: [TN (thermonetural: constant 24°C; ad libitum access to feed), PFTN (pair-fed thermoneutral: constant 24°C; limit-fed based on previous HS daily feed intake), or HS (cyclical 28°C nighttime, 33°C d 0 to 7, 33.5°C d 7 to 14, 34°C d 14 to 21, 34.5°C d 21 to 28, 35°C d 28 to 35 daytime; ab libitum access to feed)] and diet [a corn-soybean meal based diet with 0% added fat (CNTR), 3% added tallow (TAL; iodine value (IV) = 41.8), or 3% added corn oil (CO; IV = 123.0)]. No interactions between environment and diet were evident for any major response criteria (P ≥ 0.063). Rectal temperature increased due to HS (HS = 39.0, TN = 38.1, PFTN = 38.2°C; P < 0.001). Heat stress decreased ADFI (27.8%; P < 0.001), ADG (HS = 0.72, TN = 1.03, PFTN = 0.78 kg/d; P < 0.001), and G:F (HS = 0.290, TN = 0.301, PFTN = 0.319; P = 0.006). Heat stress barrows required 1.2 Mcal of ME intake more per kg of BW gain than PFTN (P < 0.001). Heat stress tended to result in the lowest ATTD of AEE (HS = 59.0, TN = 60.2, PFTN = 61.4%, P = 0.055). True total tract digestibility of AEE of CO-based diets (99.3%) was greater than that of CNTR (97.3%) and TAL-based diets (96.3%; P = 0.012). Environment had no impact on TTTD of AEE (P = 0.118). Environment had no impact on jowl IV at market (HS = 69.2, TN = 69.3, PFTN = 69.8 g/100 g; P = 0.624). Jowl IV at market increased with increasing degree of unsaturation of the dietary fat (CNTR = 68.5, TAL = 68.2, CO = 71.5 g/100 g; P < 0.001). Heat stress decreased mRNA abundance of ATGL and HSL (P ≤ 0.041). HS and CO increased mRNA abundance of SCD (P ≤ 0.047), and CO increased abundance of FASN (P = 0.011). In conclusion, HS does not alter the pig’s response to dietary fat. However, HS leads to reduced ADG, ADFI, G:F, caloric efficiency, and a suppression of mRNA abundance of genes involved in the lipolytic cascade, which resulted in a phenotype that was fatter than PFTN.
Copyright Owner
American Society of Animal Science
Copyright Date
2016
Language
en
File Format
application/pdf
Recommended Citation
Kellner, T. A.; Baumgard, Lance H.; Prusa, Kenneth J.; Gabler, Nicholas K.; and Patience, John F., "Does heat stress alter the pig's response to dietary fat?" (2016). Animal Science Publications. 809.
https://lib.dr.iastate.edu/ans_pubs/809
Included in
Agriculture Commons, Animal Experimentation and Research Commons, Animal Sciences Commons, Biochemical Phenomena, Metabolism, and Nutrition Commons, Genetics Commons
Comments
This is a manuscript of an article published as Kellner, T. A., L. H. Baumgard, K. J. Prusa, N. K. Gabler, and J. F. Patience. "Does heat stress alter the pig's response to dietary fat?." Journal of animal science 94, no. 11 (2016): 4688-4703. doi:10.2527/jas.2016-0756. Posted with permission.